摘要:
A coating and devices using the coating are provided. The coating is applied in liquid form and dried or otherwise cured to form a durable adherent coating resistant to high temperatures and having optional hydrophobic properties. The coating formulation contains an aqueous formulation of silica, one or more fillers, and sufficient base, (e.g., potassium hydroxide), to have a pH exceeding about 10.5 during at least part of the formulation process. The formulation may contain a compound(s) that affects surface free energy, energy to make the cured coating hydrophobic. Such compounds include silanes containing halogens (e.g., fluorine or chlorine) and in particular silanes containing one or more hydrolyzable groups attached to at least one silicon atom and a group containing one or more halogens (e.g., chlorine or fluorine). A medical instrument (e.g., electrosurgical instrument) may be at least partially covered by a coating using the formulation.
摘要:
A method and system for determination of dimension related information such as volumetric flow rate(s) of a fluid flowing through a channel. In one implementation, the method and system analyzes temporal changes in a moving fluid's velocity profile to calculate the fluid channel dimensions. In turn, the fluid channel dimensions and the fluid velocity profile data may be combined to calculate the volumetric flow rate of the fluid flowing through the channel. In this regard, the geometry of the channel can be characterized using dimensionless variables that relate dimensions, such as the radius across a circular cross-section, to the largest extent of a dimension. For example, in the case where the channel is a cylindrical tube and a pressure gradient is applied long enough for the fluid to have reached a steady state, the dimensionless radius will be the radius at any point divided by the overall radius of the tube. One or more dimensionless variables can be used to characterize geometries: for instance, one dimensionless radius characterizes a circular tube and two dimensionless terms characterize an elliptical tube (one for the major axis and one for the minor axis). The time required for velocity profiles to change from one shape to another may be characterized by dimensionless time. Dimensionless time, in turn, uses the fluid's viscosity and density along with time and overall channel dimensions and may be used in combination with at least one velocity profile to calculate the volumetric flow rate of the fluid flowing through the channel.
摘要:
A remotely programmable infusion system for administering liquid to a patient includes an infusion pump unit having a pump for infusing liquids operated by means of a control including a programmed processing unit and a memory chip. The processing unit operates in accordance with delivery program data stored in the memory circuit for executing an infusion delivery sequence. An output circuit is operatively disposed between the processing unit and the pump unit to control operation of the pump unit in accordance with the infusion delivery sequence. A wireless data communication circuit is operatively connected to the control for transmitting and receiving data. A programmer remote from the pump unit includes a programmed processing unit, a memory circuit, a user interface operatively associated with the processing unit for entering program commands and configuring delivery program data for storage in the memory circuit and a modem circuit operatively connected to the processing unit for transmitting and receiving data to and from the infusion pump unit. A remote communication interface unit includes a pump interface operatively communicating, in use, with the pump wireless data communication circuit, a programmer interface, including a modem circuit operatively communicating, in use, via a telephone line with the programmer modem circuit and a control circuit operatively connected to the pump interface and the programmer interface for channeling data between the pump interface and the modem circuit.
摘要:
An improved electrosurgical instrument includes a body having more than two electrodes with at least two electrodes having alternating current power supplied to them provide a bipolar alternating current configuration and employ a means other than electrode spacing for reducing or preventing accumulation of eschar. The electrodes are separated from each other using electrically insulating materials such that electric current does not flow between at least two of the bipolar alternating current electrodes unless they contact at least one other electrically conductive medium, such as patient tissue. The conductor edge portion and insulation layer each have geometric shapes and composition to reduce or eliminate the production of smoke and eschar and reduce tissue damage. The outer profile of the insulation layer and conductive element are configured to facilitate the flow of electrosurgical decomposition products away from the conductor edge where they are formed.
摘要:
An electrosurgical instrument includes a conductive element in the form of a needle that is surrounded by an insulation layer except at a conductor tip portion of the conductive element. The conductor tip portion and insulation layer each have unique geometric shapes and composition of the parts to reduce or eliminate the production of smoke and eschar and reduce tissue damage. The electrosurgical needle electrode is configured to concentrate the flow of electrosurgical at the tip region.
摘要:
A signal processing utility is disclosed involving time-to-frequency domain transforms for applications including medical diagnostic signal processing. Such transforms can be used to define a continuous spectral density function or other spectral density function including nonzero values at irregularly spaced frequency intervals. The invention thereby enables more accurate representation of certain real spectra and reduced spectral broadening. The utility also accounts for digitization errors associated with analog-to-digital conversion. The invention has particular advantages with respect to medical contexts where the received signal has a changing spectral content as a result of interaction of an interrogating signal with moving physiological material such as blood flowing through an artery.
摘要:
A coating and devices using the coating are provided. The coating is applied in liquid form and dried or otherwise cured to form a durable adherent coating resistant to high temperatures and having optional hydrophobic properties. The coating formulation contains an aqueous formulation of silica, one or more fillers, and sufficient base, (e.g., potassium hydroxide), to have a pH exceeding about 10.5 during at least part of the formulation process. The formulation may contain a compound(s) that affects surface free energy, energy to make the cured coating hydrophobic. Such compounds include silanes containing halogens (e.g., fluorine or chlorine) and in particular silanes containing one or more hydrolyzable groups attached to at least one silicon atom and a group containing one or more halogens (e.g., chlorine or fluorine). A medical instrument (e.g., electrosurgical instrument) may be at least partially covered by a coating using the formulation.
摘要:
A method and system for determination of dimension related information such as volumetric flow rate(s) of a fluid flowing through a channel. In one implementation, the method and system analyzes temporal changes in a moving fluid's velocity profile to calculate the fluid channel dimensions. In turn, the fluid channel dimensions and the fluid velocity profile data may be combined to calculate the volumetric flow rate of the fluid flowing through the channel. In this regard, the geometry of the channel can be characterized using dimensionless variables that relate dimensions, such as the radius across a circular cross-section, to the largest extent of a dimension. For example, in the case where the channel is a cylindrical tube and a pressure gradient is applied long enough for the fluid to have reached a steady state, the dimensionless radius will be the radius at any point divided by the overall radius of the tube. One or more dimensionless variables can be used to characterize geometries: for instance, one dimensionless radius characterizes a circular tube and two dimensionless terms characterize an elliptical tube (one for the major axis and one for the minor axis). The time required for velocity profiles to change from one shape to another may be characterized by dimensionless time. Dimensionless time, in turn, uses the fluid's viscosity and density along with time and overall channel dimensions and may be used in combination with at least one velocity profile to calculate the volumetric flow rate of the fluid flowing through the channel.
摘要:
A surgical system that applies electrical energy to obtain predetermined surgical effects while improving the control of the application of the energy that is supplied by electrosurgical generators. In one embodiment, a surgical assembly interfaces with and receives power from an electrosurgical generator for executing a first electrosurgical procedure. This surgical assembly may employ a shunt circuit between its power and return lines for providing in effect a voltage limitation and/or to allow a constant power electrosurgical generator to execute an at least substantially constant voltage electrosurgical technique. The electrosurgical assembly may also include a return coupler for directing energy from the patient back to the electrosurgical generator, which in turn may include a dielectric material which interfaces with the patient and which at least initially conveys the return energy via one or more electric fields versus conduction.
摘要:
A surgical system that applies electrical energy to obtain predetermined surgical effects while improving the control of the application of the energy that is supplied by electrosurgical generators. In one embodiment, a surgical assembly interfaces with and receives power from an electrosurgical generator for executing a first electrosurgical procedure. This surgical assembly may employ a shunt circuit between its power and return lines for providing in effect a voltage limitation and/or to allow a constant power electrosurgical generator to execute an at least substantially constant voltage electrosurgical technique. The electrosurgical assembly may also include a return coupler for directing energy from the patient back to the electrosurgical generator, which in turn may include a dielectric material which interfaces with the patient and which at least initially conveys the return energy via one or more electric fields versus conduction.